Photographic developer and method of developing



Patented Dec. 5, 1933 PATENT OFFICE PHOTOGRAPHIC DEVELOPER METHOD OF DEVELOPING Marion 0. Reed, Charleston,

The B. F. Goodrich Company,

W. Va., assignor to New York, N. Y.,

a corporation of New Iork No Drawing. Application March 23, 1931 Serial No. 524,759

14 Claims.

This invention relates to the art of photography and particularly to the development of latent images in silver halide photographic emulsions.

It has been the general practice to develop silver halide photographic emulsions such as those on the familiar dry plates, photo graphic films, bromide and gas-light papers, etc., by immersing them in a mildly alkaline solution of an organic reducing agent such as hydroquinone, pyrogallol, monomethyl p-aminophenol, glycine, etc. The chief object of this invention, then, is to provide a new class of developing agents which exhibit certain distinct advantages over the previously known developers. Another object is to provide a class of developers which are far less expensive somewhat greater proopers and the superior resultsattained by their 7 use.

As a specific example of one embodiment of this invention, a developing solution is prepared containing as developer m-methyl p-hydroxy N-phenyl morpholine CHI-CH1 than the ones which are now in common use.

Other objects will be evident from the following description of the invention.

The new developers which are employed in accordance with this invention are members of a class of substances having the general formula where the dotted line indicates the atoms required to complete the heterocyclic ring, R is an arcmatic nucleus, and X is a reducinggrouping such as .a hydroxyl or amino group. The preferred members of the class are compounds in which the heterocyclic ring contains an oxygen or sulphur atom and in which X is a hydroxyl group, such as the hydroxy-aryl morpholines. The following substances, for example, are typical members of the class described above: p-hydroxy N-phenyl morphollne, m-methyl p-hydroxy N-phenyl morpholine, m-methoxy p-hydroxy N- phenyl morpholine, m-hydroxy N-phenyl morpholine, o-hydroxy N-phenyl morpholine, hydroxy N-naphthyl morpholine, 'hydroxy N- biphe+ nyl morpholine, dihydroxy N-phenyl morpholine, amino hydroxy N-phenyl morpholine, ethylamino hydroxy N-phenyl morpholine, hydroxy N-phenyl thiomorpholine, hydroxy N-phenyl piperidine, p, p'-dihydroxy, N, Ndiphenyl piperazine, hydroxy 1.4 phenylene dimorpholine,.hydroxy N-phenyl pyrrole, hydroxy N-phenyl tetra-hydro pyrrole, hydrox N-phenyl hydroxyquinoline, p-amino N- phenyl morpholine, diamino N-phenyl morpholine, monomethyl dlamino N-phenyl morpholine, etc.

The new developers of the class described above may be used for the development of photographic exposure to light are CHI-CH:

according to the following formula:

. Parts Sodium sulphite 3 Developer '7 Sodium carbonate 6 -Water 1000 Plates or films which have been given a normal developed by immersion in the solution for from 15 to 25 minutes at a temperature of about 18 C. (65 F.).' They are then washed, fixed in a solution of sodium hyposulphite and washed thoroughly, in the usual manner. The photographic reproductions obtained by this process are soft and pleasing, well brought out by the action of the developer, while at the same time the contrast is good and sharp and the whites are clear. The new develexposure, good results being obtained even with emulsions which are somewhat under or over-i exposed.

The new developers of this invention are admirably adapted for tank development, because of their tendency to correct the effects of improper, exposure. They are particularly desirable for landscape or portrait work where the ability to reproduce detail is of greater importance than the production of the utmost degree of contrast. They may be kept in stock almost indefinitely, either dry or in the form of a solution, are far more stable than the majority ofthe developers now in common use, and do not deteriorate on'standing, even in moderately'strong sunlight.

Although a specific embodiment of the invention has been described ticularity, it is to be understood that this invention is not limited thereby, but that it 18 ll"- the details being oper allows an unusual latitude in the degree of for they with considerable porceptible of numerous variations within the scope of the appended claims, as will be obvious to those skilled in the art. In particular, the new developers of this-invention may be used in conjunction with other known developers, or with other salts, acids or alkalies to modify the properties of the developing solution or of the photographic images obtained thereby. Such modifications are well known expedients and need not be described here.

This invention is a continuation in part of my copending application Serial No. 442,043, filed April 5, 1930.

I claim:

1. A photographic developer comprising a solution of a compound having the structural formula where the dotted line indicates the atoms required to complete the heterocyclic ring, R is an aromatic nucleus, and X is a hydroxyl or amino group.

2. A photographic developer comprising a solution of a compound having the structural formula 0 1 \NR0H 6. A photographic developer comprising a solution of m-methyl p-hydroxy N-phenyl morpholine.

7. A photographic developer comprising a dilute aqueous solution or a hydroxy N-aryl morhn pholine.

I 8. A photographic developer comprising a dilute alkaline aqueous solution of a hydroxy N-aryl morpholine.

9. A process of developing photographic images which comprises treating a silver halide photographic emulsion which has been exposed to the light with a compound having the structural formula where the dotted line indicates the atoms required to complete the heterocyclic ring, R is an 'where the dotted line indicates the atoms required to complete a six-membered, saturated, heterocyclic ring, and R is an aromatic nucleus.

11. A process of developing photographic images which comprises immersing a silver halide photographic emulsion which has been exposed to the light in an aqueous solution comprising a hydroxy N-aryl morpholine.

' 12. A process of developing photographic images which comprises immersing a silver halide photographic emulsion which has been exposed to the light in an aqueous solution comprising a hydroxy N-aryl morpholine in which the aryl group contains only one aromatic ring.

13. Alprocess of developing photographic images which comprises immersing a silver halide photographic emulsion which has been exposed to the light in a dilute, aqueous, alkaline solution comprising a p-hydroxy N-aryl morpholine in which the aryl group contains only one aromatic ring.

14. A process of developing photographic images which comprises immersing a silver halide photographic emulsion which has been exposed to the light in an aqueous, alkaline solution comprising m-methyl p-hydroxy N-phenyl morpho- MARION o. REED. 

